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received water from groundwater sources. <br />Along the 110 potential bottomland sites, we estimated 13.4 miles (21.6 <br />km) of natural levees and 26.6 miles (42.9 km) of human-made dikes and levees. <br />Of the various bottomland habitat types, 41 were floodplain terraces, 23 <br />gravel-pit ponds, 22 side channels, and 16 canyon mouths. The remaining <br />flooded habitat types consisted of 13 floodplain depressions and one oxbow. <br />All 13 depressions were located between Moab Slough and the Green River <br />confluence. Three of these depression habitat sites (rm 50.9-52.5 [rkm 82- <br />84], rm 33.2-35.6 [rkm 53-57], and rm 17.5-18.7 [rkm 28-30]), may be important <br />off-channel habitats for razorback sucker drifting downstream if an expected <br />or planned upstream spawning area is identified. Although these areas are wet <br />during high water, they appear isolated from the river in photos and water <br />enters only by groundwater infiltration and, therefore, fish do not have <br />access to these areas. Further on-ground investigation of these areas is <br />needed to determine water depth during runoff to monitor water duration, and <br />to evaluate if fish can access these areas during high water. <br />Gunnison River. There were 48 bottomland habitat sites with a potential <br />(historical) of 3,227 acres (1,306 ha) along the Gunnison River (rm 0-75 [rkm <br />0-121]) in 1993 (Appendix D; Table D.2.). Of this total, 828 acres (335 ha; <br />41 sites) were inundated during the May and June high water period and 161 <br />acres (459 ha) in the September low-water flow period. <br />In the Gunnison River, there was only one general area where bottomland <br />habitats were concentrated. This was in the 17-mile stream reach in the <br />Delta, Colorado, area that extends from Roubideau Creek upstream to Austin (rm <br />50-67 [rkm 81-108]). There were 1,739 acres (705 ha) of potential floodplain <br />habitat in this 17-mile reach. The remaining 50 miles of warmwater stream <br />reach downstream of Roubideau Creek can be predominantly classified as canyon- <br />bound with few bottomland habitat sites. <br />Eighty-five percent of the 41 sites flooded in May had a hydrological <br />connection to the river, whereas 76% (13 sites) of the 17 sites still wet in <br />September were connected to the-river (Appendix E; Tables E.14 to E.16.). <br />Although 41 of 48 sites were inundated during May and June, only 17 sites had <br />one surface connection to the river and 16 sites had both and up- and <br />downstream surface connection. Thirteen of the May flooded sites received <br />some water from a gravity-fed (irrigation) water source. <br />Along the 48 potential bottomland sites, we estimated 1.2 miles (2 km) <br />of natural levees and 8.3 miles (13.4 km) of human-made dikes and levees. Of <br />the various bottomland habitat types, 35 were floodplain terraces, six gravel- <br />pit ponds, three oxbows, and two side channels. The remaining habitat types <br />consisted of one floodplain depression and one canyon mouth. <br />Site Scoring and Prioritization <br />All bottomland habitat sites identified, 135 in the Green River Drainage <br />(Appendix F; Table F.1.) and 158 in the Colorado River drainage (Appendix F; <br />20